BMW patented a new lightweight frame for the upcoming three-cylinder engine?

BMW Motorrad is rumored to be developing a new lightweight frame for the upcoming three-cylinder motorcycle.

The patent application shows a subframe that bolts directly to the engine using massive bolts that also connect the cylinder head to the block, resulting in a design that is lighter and more compact than a conventional assy.

According to the patent sketches, the design features a conventional mounted engine, but instead of being wrapped in aluminum or steel construction, a simple cast alloy front axle is bolted directly to the engine. This provides a direct connection to the steering head, allowing the rear fork to rotate on the derailleur, with the motor acting as a stressed member.

The design aims to minimize the width of the motorcycle, which is common for machines with transversely mounted in-line engines. It also reduces the number of parts and weight, making the design more efficient. BMW’s patent hints at using this new assy design for a three-cylinder engine, which will further reduce the size of the bike, making it more aerodynamic and less complex than bikes with V-twin or V-4 engines.

BMW had successful four-cylinder engines such as the S 1000 RR, but a three-cylinder engine would be in, giving the company an opportunity to make a bike in the future. BMW has previously explored the use of three-cylinder engines, notably in its MotoGP project in the early 2000s. The project produced a prototype that was later scrapped due to technical problems, but provided the company with the knowledge base needed to develop the S 1000 RR.

Since then, rumors have swirled about a three-cylinder BMW sports bike, with little evidence to back them up. However, all of this provides the first real indication that such a motorcycle is in development.